Semaphore switch-stand.



No. 824,870. 7 PATENTED JULY 3, 1906. J. D. ISAAGS, W. W. SLATER & M} R. DANIELS.

SEMAPHORE SWITCH STAND. APPLICATION FILED MAB.24, 1906.

2 S HEETSSHEET 1.

No. 824,870. PATENTED JULY 3, 1906. J. D. ISAAOS, W. W. SLATER & M. R. DANIELS.

SEMAPHORE SWITCH STAND.

APPLICATION FILED MAR. 24, 1906 2 SHEETS-SHEET 2.

in zen firs 1n; NnRRls PEI-Ens ca" WAsHINnTaN, n. c.

UNITED STATES PAlFINT OFFICE. i I'm JOHN D. ISAACS, OF OAKLAND, AND WILLIAM W. SLATER AND MARK R. DANIELS, OF SAN FRANCISCO, CALIFORNIA.

SEMAPHORE SWITCH-STAND.

Specification of Letters Patent.

Patented July 3, 1906.

To all whom it 777/6LZ/ concern:

Be it known that we, JOHN D. IsAAos, of the city of Oakland, Alameda county, and WILLIAM W. SLATER and MARK R. DANIELS, of the city and county of San Francisco, State of California, have invented certain new and useful Improvements in Semaphore Switch-Stands and we do hereby declare the following to be a full, clear, and exact description of the same.

Our invention relates to the class of semaphore switch-stands; and it consists, in connection with the lever having the double function of operating both the track-switch and the semaphore-spectacles, of intervening mechanism for effecting the change of the spectacles only approximately at the moment the track-switch reaches or departs from a safety position.

The object of our invention is to insure the change of the spectacles at the most timely moment, which moment is that at which the switch reaches or departs from safety, as we shall hereinafter demonstrate.

Referring to the accompanying drawings, Figure 1 is an elevation, partly in section, of our semaphore switch-stand, showing the back spectacle at safety, the front spectacle and blade being removed. Fig. 2 is an elevation, partly in section, of the switch-stand at right angles to the elevation of Fig. 1. Fig. 3 is a plan view of our semaphore switchstand on a smaller scale. Fig. 4 is an elevation of the same, the spectacles and blade being at safety, dotted lines showing the movement to danger. Fig. 5 is a side View of the operatin mechanism, showing the toggle in position for safety. Fig. 6 is a similar view showing the upper limit of the rise of the toggle. Fig. 7 is a similar view showing the continued movement of one of the links of the toggle without affecting the semaphore.

l is the switch-stand base, upon which in suitable bearings 2 is moimted the rocking semaphore-shaft 3. To one end of this shaft is connected the switch-lever 4, having a pin 5, on which is mounted the connecting-rod 6, which is here shown broken away, but which may be supposed to extend to and be connected with the throw-rails of the trackswitch, which it is deemed unnecessary herein to show in the usual manner.

Rising from the stand-base 1 is the semaphore-post 7, which carries at its top the lantern 8, having the usual plain-glass lights 9.

Mounted to rock in the upper portion of the post 7 is the spectacle-shaft 10,, on the ends of which are the spectacle-castings 11, one being the front spectacle and the other the back spectacle. Each casting 11 carries the usual red glass 12 and the reen glass 13, adapted to be severally aline with the lantern-lights 9, as usual, according to the necessities of the case. The movement of the spectacles is due to the rocking of shaft 10, which rocking is effected by means of the crank 14 on said shaft and the up and down rod 15 in the post 7.

To the spectacle-casting is fitted the usual semaphore-blade 16 for a dayli ht-signal.

The parts thus far describe are those in general of the usual dwarf semaphore switchstand.

Heretofore in such devices the duplex function of the switch-lever 4to Wit, that of operating the track-switch and that of operating the spectacleshas been open to the objection that the two operations or movements are what may be termed relatively synchronous throughoutthat is, the throw-rails of the switch are going through their movement at the same relative rate as the spectacles are erforming their movement. The result 0 this may be seen from an exampleas, for instance, suppose the spectacle and the switch to be set for safety in a particular case. Now when the switchlever commences its movement toward danger both the spectacle and the switch begin their movement toward a like condition; but while the spectacle may take some minutes prior to reaching its limit, where it shows danger, the switch instantly becomes dangerous the moment it begins to depart from safety. The spectacle and switch are therefore not in harmony at the start.

The reverse illustration may also be given to wit, suppose the spectacle and switch be set for danger. Then in throwing the spectacle for safety it departs from danger some moments before the switch has reached safety, for of course the switch is never safe except at its limit, and the slightest movement from this limit represents danger. To obviate this difficulty, we destroy by our invention this relative synchronosity of the two movements by giving to the spectacle itsfull functional movement by a quick change, timed approximately to the limit of the switch-throw, whereby the spectacle indicates with the maximum accuracy the instant the throw-rails of the switch reach safety or depart therefrom. In the present case the means preferred are as follows: These consist of a toggle comprising a pair of links, the one, 18, being pivoted to a fixed bearing 17 on the base 1 and the other, 19, being pivoted. to a crank 20 of the shaft 3. The up-and-down rod 15 is connected with this toggle, as shown. The arrangement of pivotal centers is such that as the crank 20 rises it lifts the toggle-joint until the latter reaches the level of the crank-axis and all the centers are alined. Then the link 18 stops, and the link 19 accompanies the crank 20 to its limit, but without further lifting the toggle-joint. Descending, the link 19 and crank 20 swing together to the alinement of all the centers, whereupon further downward movement causes the joint of the toggle to descend to its initial position. The end of link 18 projects, as shown at 21, beyond its connection with link 19, and said end is adapted to contact with a stop-pin 22 on the toggle-joint when the centers are alined, whereby said joint is insured against further upward movement. The arrangement of this toggle relatively to the parts which operate it and which it operates is such that when the switch-lever is substantially horizontal the crank 20 is likewise horizontal, and the joint of the toggle is depressed. In this position the spectacles are set for safety and the switch is closed. Now upon lifting the switch-lever the first effects are twoto wit, to begin to throw the switch-rails and at the same time-that is, at the very beginning of the movement of the switchto instantly throw the spectacles fully to danger. This is due to the action of the crank 20 on the two toggle-links 18 and 19, raising their oint, and thereby lifting the rod 15, which operates the spectacles. Thereafter the continued movement of the switch-lever, while it fully operates the switch, has no effect on the spectacles, because the joint of the two links can travel no higher than the axis of shaft 3. Thereafter the link 1 9 simply turns on its pivotal connection with link 18 and accompanies crank 20 to the full throw of the latter. Thus the semaphore-spectacles are fully operated the instant the switch begins to move. Reversely, when the switch-lever is thrown down again there is at first only one effectnamely, to begin to operate the switch; but the spectacle remains at danger and should do so, because the switch is not safe until it reaches its limit; but when about to reach this limit, and consequent safety, the joint of the two links begins to descend, and just as the switch closes the spectacles are moved to safety. Thus the semaphore remains at danger until the switch reaches safety, when at the same instant it is operated to indicate the fact.

Having thus described our invention, what we claim as new, and desire to secure by Letters Patent, is

1. In a semaphore switch-stand, the combination of a switch-lever, a connection from the lever to operate the switch, a semaphorespectacle, a rod and connections to operate the spectacle, and intervening connections between the switch-lever and spectacle-rod adapted to'operate the spectacle only, approximately, at the moment the switch reaches or departs from the safety position, consisting of a rock-shaft to which the switchlever is connected, a toggle comprising a pair of pivotally-connected links to which the spectacle-rod is connected, and a crank on the nick-shaft pivotally connected to said togg 2. In a semaphore switch-stand, the combination of a switch-lever, a connection from the lever to operate the switch, a semaphorespectacle, a rod and connections to operate the spectacle, and intervening connections between the switch-lever and s ectacle-rod adapted to operate the spectac e only, approximately, at the moment the switch reaches or departs from the safety position, consisting of a rock-shaft to which the switchleveris connected, a toggle comprising a pair of pivotally-connected links to which the spectacle is connected, a fixed bearing to which one of said. links is pivotally connected, and a crank on the rock-shaft pivotally connected to the free extremity of the other of said links, whereby the oint of the tog le is lifted to and depressed from the level of the crank-center.

3. In a semaphore switch-stand, the combination of a switch-lever, a connection from the lever to operate the switch, a semaphores ectacle, a rod and connections to operate tfie spectacle, and intervening connections between the switch-lever and spectacle-rod adapted to operate the spectacle only, ap-

proximately, at the moment the switch.

IIO

In Witness whereof we have hereunto set our hands.

JOHN D. ISAAOS. WILLIAM W.-SLATER. MARK R. DANIELS. Witnesses to signatures of Isaacs and Slater:

JAMES C. YOUNG, ARCHIE W. HEWITT Witnesses to signature of Daniels WALTER FARNHAM, D. G. KLINEFELTER. 

